<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        //1.写入浏览器的body区域
        document.write("hello JS..."); 

        //2.弹出框
        window.alert("hello Js222222222");
        alert("hello Js222222222");//windows对象可以省略

        //3.控制台
        console.log("hello JS2333333");
    </script>
</body>
</html>